Demand for integrated circuits (ICs) in portable electronic applications has motivated greater levels of semiconductor device integration. Many advanced semiconductor devices in development leverage non-silicon semiconductor materials, including compound semiconductor materials (e.g., GaAs, InP, InGaAs, InAs, and III-N materials). These non-silicon material systems may be employed to fabricate metal oxide semiconductor field effect transistors (MOSFETs) and other forms of high mobility transistors (HEMT). Non-silicon material systems are also useful for photonics (e.g., LEDs), photovoltaics, and sensors, one or more of which may be useful to integrate with silicon-based devices in an electronic device platform.
One technique for fabricating non-silicon transistors includes forming a non-planar, non-silicon crystalline device region (e.g., a fin channel region) over a silicon substrate. The device region material and/or an underlying material form at least one heterostructure with the substrate. While such heterostructures in theory enable monolithic integration of high performance N-type devices with conventional silicon-channeled P-type devices, divergent device architectures have thus far made high volume manufacturing of CMOS circuits employing heteroepitaxial N-type devices impractical.